The problem, Engroff said during the “transparency” panel at OMMA RTB, is that none of the
programmatic media-buying marketplace is truly open, not even “open exchanges” in powering the RTB marketplace.

While it is “fashionable” to make the Wall
Street/Madison Avenue comparison, Engroff says the main difference is “there is no Bloomberg terminal for online media,” and therefore no way to see the total “liquidity” of
the online marketplace, meaning the total volume of ad impressions available and traded.

Because no buyer or seller can see the complete supply and demand in RTB, Engroff said,
“The open exchange is already a dark pool.”

Fellow panelist, Mediasmith’s Marcus Pratt, agreed that “there are a lot of differences in how we buy” vs. Wall
Street’s traders.

Interestingly, the main “transparency” issue -- at least from a publisher’s point-of-view -- have less to do with the quality of the
impression being traded (you know, like whether someone actually viewed it), so much as it’s about the price being paid for it.

“From a publishing perspective, pricing is probably is
the biggest black hole,” Sean Holzman, Chief Brand Development Officer at Bonnier Corp., said, adding, “For us, it’s probably the one where we’re having the hardest
time.”